This invention relates in general to ball joints, such as are commonly used in vehicular steering and suspension applications to transmit force between a steering mechanism and a steered wheel of a vehicle. In particular, this invention relates to a device that generates an externally perceptible indication when a predetermined amount of wear has occurred within a ball joint and additionally provides a positive retainer for preventing accidental separation of the components of the ball joint as a result of such wear.
Ball joints are well known structures that are used in a variety of mechanical linkages. For example, ball joints are commonly used in vehicular steering and suspension assemblies to transmit force between a steering mechanism and a steered wheel of a vehicle. A typical ball joint includes a ball stud that is received within in a lubricated socket. The ball stud includes a spherically-shaped head portion having an elongated shaft portion extending therefrom. The spherically-shaped head portion of the ball stud is received within and cooperates with a corresponding spherically-shaped recess formed in the socket. This arrangement positively connects the ball stud to the socket so as to permit forces to be transmitted therethrough, but also allows the ball stud to pivot in any direction relative to the socket.
It has been found that after a period of use, the cooperating portions of the ball stud and the socket of the ball joint will experience wear. Such wear can create undesirable looseness between the ball stud and the socket of the ball joint, resulting in the generation of noise and misalignment between the ball stud and the socket. In extreme cases, such wear can contribute to or cause the accidental separation of the ball stud from the socket, resulting in a total failure of the ball joint. Unfortunately, because the spherically-shaped head portion of the ball stud is received within the corresponding spherically-shaped recess formed in the socket, it is often difficult to determine how much wear has occurred within the ball joint without removing the ball joint from its application and disassembling the ball stud and the socket for inspection. Such removal and disassembly is time consuming and expensive. Thus, it would be desirable to provide a device that generates an externally perceptible indication when a predetermined amount of wear has occurred within the ball joint and additionally provides a positive retainer for preventing accidental separation of the components of the ball joint as a result of such wear.